Sonic the Hedgehog Spinball, or Sonic Spinball (ソニック・スピンボール Sonikku Supinbōru?), is a pinball video game in the Sonic the Hedgehog series. It was originally released for the Sega Mega Drive/Genesis in 1993 and later ported to the Sega Game Gear and Sega Master System in 1995.
The term "Spinball" is a portmanteau on pinball and "spin dash", a move Sonic performs. It, along with Dr. Robotnik's Mean Bean Machine were the only two Sonic games released to use characters and elements from the Adventures of Sonic the Hedgehog and Sonic the Hedgehog cartoons.
Sonic Spinball is essentially a pinball simulation featuring Sonic as the "ball". The main difference from traditional pinball game is the ability to influence Sonic's movement somewhat while moving, although flippers are still the primary source of movement. In a few rare instances, the player can control Sonic on foot, but for the majority of the time he is rolled into a ball and controlled by the flippers.
The game features four large pinball tables: a sewer level, a geothermal power station, a robot factory, and a launchpad system. The player must guide Sonic through each of the four levels and collect all of the Chaos Emeralds, then fight Dr. Robotnik. Once all of the Chaos Emeralds in a level are collected, Sonic gains access to the boss room and has to defeat a boss to advance onwards. Sonic will lose a life if he falls into certain traps such as lava, slime, or monsters, and the game ends when the player loses all their lives.
Dr. Robotnik has assumed control of Mt. Mobius and turned it into a mechanical base, named the "Veg-O-Fortress". Utilizing energy produced by the magma flowing under the volcano, it has the power to transform helpless animals into robot slaves. Sonic the Hedgehog and Miles "Tails" Prower fly onto the scene, but Sonic is knocked off the wings of Tails' airplane by a blast from the fortress. He falls into the water, but survives and ends up in the Veg-O-Fortress. Sonic proceeds to work his way through its elaborate "Pinball Defense System", while collecting the Chaos Emeralds, in order to destroy, and escape, the fortress.